Four small bombs exploded in Colombia in what police said may have been a protest by leftist guerrillas against the presence of U.S. President Barack Obama in the country for the Summit of the Americas.
"There are windows broken, but nobody hurt or killed," the source added.
Obama landed in Cartagena, on Colombia's northern coast far from Bogota, earlier on Friday. "It might be a protest by an urban guerrilla cell against Obama," the source told Reuters.
Local authorities in Cartagena told NBC News that two small bombs also went off in Cartagena, about a 45-minute drive away from the summit site itself.
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